mongoDB-示例代码

"""
pymongo模块操作示例
用于数据增删改查索引聚合方法的参考
"""

from pymongo import MongoClient

# 　创建数据库连接
conn = MongoClient('localhost', 27017)

# 　创建数据库对象和集合对象
db = conn.stu
myset = db.class4

# 　数据操作

# *********** insert **************
# myset.insert_one({'name':'张铁林','King':'乾隆'})

# myset.insert_many([{'name':'陈道明','King':'康熙'},
#                    {'name':'张国立','King':'康熙'}])

# myset.insert({"name":'唐国强',"King":'雍正'})

# myset.insert([{"name":'陈建斌',"King":'雍正'},
#               {"name":'聂远','King':"乾隆"}])

# myset.save({'_id':1,'name':'吴奇隆',"King":'四爷'})
# myset.save({'_id':1,'name':'郑少秋',"King":'乾隆'})

# ************* find **************

# 　所有的操作符加引号，作为字符串表达
cursor = myset.find({'name': {'$gt': '唐国强'}}, {'_id': 0})

# 　循环遍历得到的每一个结果都是文档字典
# for i in cursor:
#     print(i['name'],'---',i['King'])

# print(cursor.next())  #　获取游标的下一个结果

# 　cursor调用limit,skip,sort后得到的仍然是结果游标对象
# for i in cursor.skip(1).limit(3):
#     print(i)

# 按照ｋｉｎｇ排序
# for i in cursor.sort([('King',1)]):
#     print(i)

# r = myset.find_one({'King':'康熙'},{"_id":0})
# print(r)

# ************** update *************
# myset.update_one({"King":'康熙'},
#                  {'$set':{"king_name":'玄烨'}})

# myset.update_many({"King":'雍正'},
#                   {"$set":{'king_name':'胤禛'}})

# myset.update({"King":'乾隆'},
#                   {"$set":{'king_name':'弘历'}},
#              multi=True)
#
# myset.update_one({"King":'光绪'},
#                  {'$set':{"name":'邓超'}},
#                  upsert=True)

# ************ delete *************
# myset.delete_one({'King':'乾隆'})
# myset.delete_many({"king_name": None})
# myset.remove({"King":'雍正'},multi=False)

# r = myset.find_one_and_delete({'King':'乾隆'})
# print(r)

# *************** index ***************
# 　参数 'name' ==> [('name',1)]
# index1 = myset.create_index('name')
# index2 = myset.create_index([('name', -1)], 
#                             name="NAME",sparse=True)
#
# print("index1 = ", index1)
# print("index2 = ", index2)

# 　删除索引
# myset.drop_index('NAME')
# myset.drop_index([('name',1)])
# myset.drop_indexes()

# 　查看索引
# for i in myset.list_indexes():
#     print(i)

# ************ aggregation **********
myset = db.class0  # 更换操作集合

pipe = [
    {'$match': {'gender': {'$exists': True}}},
    {'$sort': {'age': 1}},
    {'$project': {'_id': 0}}
]

cursor = myset.aggregate(pipe)

for i in cursor:
    print(i)

# 关闭连接
conn.close()